Mechanical properties and microstructures of Al2O3/AlTiC/ZrO2/diopside ceramic composite

Al, Al3Ti and TiC in the form of AlTiC master alloys and ZrO2 particles were incorporated into alumina matrix ceramic materials. Composite of Al2O3/TiC/ZrO2/AlN were fabricated by hot-pressing process, during sintering new phase of A1N was produced by chemical reactions between Al and N2(the protective atmosphere). Some Al2Ti4C were brought into existence as the chemical reactions among Al, TiC and Ti produced by the decomposition of Al3Ti. The hardness, fracture toughness and bending strength of the composites were tested. Meanwhile, the influences of 1lvol% addition of diopside, on densification rate and mechanical properties of alumina matrix ceramic materials were analyzed. The effects of fracture mechanism on mechanical properties of the composites and refining performances of AlTiC master alloys were investigated.